For seven long years Posh have waited for the greatest of all their rivals to catch up, to emerge from a very long neighbourly shadow, to be deemed good enough to grace the ABAX Stadium turf again.

But those Posh fans who scoffed in amusement as Cobblers lurched from crisis to crisis on and off the field in recent times were misguided. If this night proved anything, it was these clubs need each other.

Never mind the result, the crackling atmosphere, the passion on display on the pitch and in the stands, the crunching, committed tackles, the sheer desire and will to win from both camps made this a memorable experience in a season that has seen too many low crowds, too many flat atmospheres and too much apathy.

Welcome back Cobblers, oh and thanks for the morale-boosting three points. If Posh don’t receive a serious pick-me-up from such a convincing victory there should be an immediate steward’s enquiry.

Posh boss Grant McCann compared a rocking stadium to the night Posh beat the dreaded MK Dons in a League One play-off semi-final in 2011. The stakes last night (October 18) were not that high, but it was still a huge game for a rookie boss and a team yet to completely win over a sceptical Posh public.

Posh striker Paul Taylor working hard on the edge of the Northampton penalty area. Photo: David Lowndes.

There were times when Posh rode their luck in their own penalty area as just a second clean sheet of the season was secured, there were times when they gave the ball away far too readily on a foul night full of strong wind and heavy rain and there were times when some poor attacking decisions ruined the chance of further goals, but for one night only that didn’t matter. This win will extend a honeymoon period, at least for another month when the teams do it all again at Sixfields.

The fickleness of football fans should never be under-estimated. While McCann was feted for a top decision to play enforcer Michael Bostwick in midfield, Cobblers boss Robert Page was condemned (his fans conveniently ignored the absence of two key midfielders) for a 3-5-2 formation that quickly unravelled against the youth, vitality and superior speed of their oppponents.

The truth, as ever, was somewhere in between. Posh deserved to win against a team that didn’t create a single notable scoring chance, but there were enough favourable bounces of the ball for the home side, particularly during a constant spell of second-half pressure, for the scoreline to be deemed flattering.

Tom Nichols’ goal eight minutes from time - his first in 13 outings which completed the scoring - was taken on the breakaway and only then could Posh really start the victory celebrations which included the inevitable taunting of visiting supporters, who by then were drenched, miserable and pretty quiet. ‘3-0, on your big day out’ poured forth from the London Road End.

A own goal for Posh courtesy of Cobblers' defender Zander Diamond. Photo: David Lowndes.

McCann stuck with his midfield diamond, but employed Bostwick at its base. enabling skipper Chris Forrester to play in a more advanced position. It was a game and occasion made for Bostwick’s combative nature and he excelled thanks to his power tackling and aerial ability.

Both sides reacted to poor weekend defeats by making four changes to their starting line-up.

But Posh started much the better, hogging possession and pinning Cobblers into their own half, helped by a strong wind and driving rain at their backs.

It wasn’t a surprise that Posh went in front after 14 minutes. But it was a surprise that Coulthirst grabbed his first goal of the season with a free near post header from Maddison’s corner.

But Cobblers reacted well to falling behind. Their wing-backs found plenty of space in which to operate, but couldn’t find the cross to match their endeavour.

Jack Baldwin produced a brilliant block to thwart Diamond’s fierce strike from a set-piece before Posh scored from another Maddison corner as pressure from Ryan Tafazolli forced Diamond to head into his own net on 37 minutes.

Gaby Zakuani, who played well, returned to Posh for the first time since his summer move, but his love of the club he left apparently didn’t extend to Coulthirst. His first act of the night was to flatten his former team-mate, although Coulthirst’s departure on the stroke of half-time was unrelated to that incident.

Coulthirst’s absence didn’t affect Posh who started the second half strongly. Taylor’s shot from an acute angle was saved by Smith and then the Posh forward should have scored after being freed by Maddison, but he delayed his shot too long and Brendan Maloney was able to make a superb goal-line block.

Cobblers eventually started to assert themselves, but they either crossed poorly or their strikers didn’t react quickly enough to convert possible opportunities.

Michael Smith did well to block a far post header from Cobblers’ substitute JJ Hooper before Posh broke away to score their third goal. Substitute Gwion Edwards made a fine run down the right and delivered the perfect cross for Nichols to volley home.

It was the perfect ending to a night to remember, watched by a bigger crowd than on the last meeting in March, 2009, when Posh were a top League One side in great form.